diff --git a/system/database/DB_utility.php b/system/database/DB_utility.php
index 9eac2ec..57356ac 100644
--- a/system/database/DB_utility.php
+++ b/system/database/DB_utility.php
@@ -417,7 +417,7 @@
 			return gzencode($this->_backup($prefs));
 		}
 
-		return '';
+		return;
 	}
 
 }
diff --git a/user_guide_src/source/database/utilities.rst b/user_guide_src/source/database/utilities.rst
index 2aeadfd..bafa08e 100644
--- a/user_guide_src/source/database/utilities.rst
+++ b/user_guide_src/source/database/utilities.rst
@@ -252,7 +252,7 @@
 	.. php:method:: backup([$params = array()])
 
 		:param	array	$params: An associative array of options
-		:returns:	string
+		:returns:	raw/(g)zipped SQL query string
 		:rtype:	string
 
 		Perform a database backup, per user preferences.